One province and three major cities in China will ban long-distance buses, authorities said Sunday, as they scramble to contain a deadly new virus that has spread across the country.

The eastern Shandong province, with a population of 100 million people, will suspend long-distance buses entering the province, state broadcaster CCTV reported, following the announcement of similar measures in the cities of Tianjin, Beijing and Xi'an.

Inter-city buses in the province will only be allowed to leave if stations have temperature screening measures, CCTV said. From 6 pm (1000 GMT) Sunday, Xi'an will suspend long-distance buses and tourist chartered buses entering the city of 10 million people, local officials said on the Twitter-like Weibo platform, following the announcement of similar measures in Tianjin and Beijing.

Inter-city taxis will be suspended, except those from the city's airport, the statement said. The measures are to stop the spread of the virus through "passenger transport by road and taxis", officials said.

Several cities and regions across China have announced travel restrictions to control the virus that has infected nearly 2,000 people and killed 56.

The strictest measures have been imposed on Wuhan, the epicentre of the outbreak, where people are not allowed to leave the city. Transport bans have been placed in many other cities in Hubei province, of which Wuhan is the capital, affecting some 56 million people.

Beijing announced it will suspend bus services entering and exiting the Chinese capital's boundary from Sunday, and the northern city of Tianjin will suspend long-distance buses and chartered buses that enter and leave the city starting Monday.

The southern city of Shantou announced a partial lockdown on Sunday, the first such measure taken outside the epicentre of the disease.

From midnight, non-emergency vehicles will be prohibited from entering the city of 5.6 million people, which is a 1,100-kilometre (680-mile) drive from Wuhan.

People arriving at Shantou train stations will be screened and "urged to return", said city authorities.

Meanwhile, the United States is arranging a flight to evacuate personnel and American citizens trapped at the epicentre of a deadly virus in central China, the US State Department said on Sunday.

The flight will leave on Tuesday from the city of Wuhan to take consular personnel to San Francisco, the department said in an email to Americans in China, warning that there would be limited space for private citizens.

"This capacity is extremely limited and if there is insufficient ability to transport everyone who expresses interest, priority will be given to individuals at greater risk from coronavirus," the department said.

Around 1,000 American citizens are believed to be in Wuhan, the capital of Hubei province, the newspaper said. France plans to evacuate its citizens stuck in Hubei by bus.

The outbreak, which has killed 56 people and infected nearly 2,000 across China, is believed to have originated in a seafood and live animal market in Wuhan.